Before working on There Will Be Blood, special-effects supervisor Steve Cremin had created flaming oil wells for Jarhead — so successfully, in fact, that effects artists at Industrial Light & Magic still use those fire elements as references for other shows. Here is his account of how the flaming geyser was created for a key scene in Paul Thomas Anderson’s period drama:

“We used petroleum products, diesel fuel and gasoline in different proportions depending on the shot. For day scenes, we used a mix that would create more smoke. Smoke doesn’t read at night, but if we wanted some night shots to be brighter, we just changed the mix.

“We made our own jet nozzle to shoot the juice through. The pumps we used were hard to find: high-pressure petroleum-transfer pumps that do a huge volume at huge pressure. They were powered by hydraulic motors, which eliminated the danger of creating sparks anywhere near the fluid. Using an electric pump with metallic parts can throw sparks all over the place, and the impellers aren’t explosion-proof, so you’re taking a heck of a chance with that kind of setup. All our power was remotely activated.

“When you do this kind of stunt, you’re subjected to environmental oversight the whole time. No fuel can be shot through the nozzle unless it’s ignited; you can’t let any fluid hit the ground, because then you’re liable for a toxic spill. Before we shot anything, we had to test the whole area to verify the levels of petroleum in the soil. Once we’d finished the stunt, we had to pull soil samples within a 150-foot radius [of the fuel jet] to prove we hadn’t added petroleum to the soil.

“Because the flames had to ignite on camera, we first ran simulated oil, a water-based non-toxic product that was okay to drop on the ground. That ran through one pump for a certain amount of time, and then we’d inject the other pump and safely follow the water with fuel we could ignite.

“We had four igniters in case any of them failed. They included electronic coils, propane poppers, pyrotechnics and, as our fourth backup, road flares below the deck. If anything shot out of the nozzle and didn’t get lit, it had to go through the flares before it hit the ground.

“The original proposal was to make the derrick out of steel and put a veneer on it that could burn. That would have allowed us to put out the fire and replace the veneer for subsequent takes, but building a steel derrick would have been more expensive and time-consuming. And Paul just prefers guerrilla-filmmaking tactics: ‘Let’s just light it up and go for it.’

“Because the derrick was made of wood, I knew that even if we managed to put the fire out, the structure would smolder through the night and possibly collapse. As it turned out, we picked a night that was about as windy as we could tolerate, and the flames all blew to one side of the derrick. We put water on it and got the flames to go out, but we couldn’t guarantee the derrick would still be there the next day, so we had to keep going to get the shot where it collapses.

“We let the derrick burn for as long as we could before we had to pull it down. The crew kept filming while Paul let the actors try different things; he’s a bit of a renegade, and he wanted to play it out to the bitter end. I was standing behind him while the derrick was crackling and popping, and he kept looking back at me to make sure it was okay to keep going. Finally, I said, ‘It’s time. If we don’t drop it, it’s going to drop on its own.’ He wanted to try one more scene that took about two minutes, and I was sure we were going to lose the derrick. But he finally said, ‘Okay, drop it.’ We had the derrick hooked up to a crane with a couple of cables that allowed us to pull a weak-knee out from under it. It dropped like a dream.

“For reverses of the actors shot the next day, we just lit up our jet nozzle again. All crewmembers anywhere near the fire wore Nomex fire-protection suits, but the actors were just wearing wardrobe that had been flameproofed. The closest actors were about 120 feet from the fire, but it was still extremely hot at that distance. Trust me, you can’t get close enough to actually get burned because it gets very uncomfortable. My guys probably got within 60 feet of the fire, and they could only stay that close for a short time.”